Power loss after warms up
Administrator
Joined: Apr 2006
Posts: 25,707
Likes: 107
From: Denver, Colorado
I just replaced the wires - good news/bad news.
Good news: It was easy!! I was worried after all the write-ups, but I was able to worm my hand behind the intake & do the job quite easily....without taking any parts off the engine. Took me just under an hour.
Enough gloating....on to the:
Bad news: The problem still exists. It ran great for 15 minutes or so (better than before). After that the problem returned.
I got it tested at AutoZone & following are the codes they gave me:
- 300 (Random cylinder misfire detected)
- 301 (Cylinder 1 misfire detected)
- 306 (Cylinder 6 misfire detected)
- 1690 (Neutral position switch circuit high input)
I also read that this could be a symptom of the CAT's going out - The post I read said to look under the truck to see if it is glowing red - Mine was not.
Any assistance is appreciated.
Good news: It was easy!! I was worried after all the write-ups, but I was able to worm my hand behind the intake & do the job quite easily....without taking any parts off the engine. Took me just under an hour.
Enough gloating....on to the:
Bad news: The problem still exists. It ran great for 15 minutes or so (better than before). After that the problem returned.
I got it tested at AutoZone & following are the codes they gave me:
- 300 (Random cylinder misfire detected)
- 301 (Cylinder 1 misfire detected)
- 306 (Cylinder 6 misfire detected)
- 1690 (Neutral position switch circuit high input)
I also read that this could be a symptom of the CAT's going out - The post I read said to look under the truck to see if it is glowing red - Mine was not.
Any assistance is appreciated.
Based on your codes and what you have described, it is not your cats.
TReK
Joined: Mar 2012
Posts: 3,171
Likes: 45
HI
I had a misfire on #1 cylinder. Turned out to be the head gasket.
If you can get this truck started, then take off the cap to the expansion tank where you put the coolant in.
If the truck pushes out coolant - then this is a bad sign.
If you hear the water fall sound while driving - this is air in your heater core.
All of this from a bad head gasket with a hair line crack possibly.
Cylinder #1 there is only about 4 to 5 mm of head gasket between the firing ring seal and the coolant jacket. Pressure goes into the coolant system and antifreeze gets into the cylinder.
#6 cylinder is not near a coolant jacket.
#6 could misfire from a sticky valve.
Well, If the wires for #1 and #6 go into the same coil pack - then I would first try to replace that coil pack (there are two).
And, give that a try.
IF that does not solve it - then I am thinking #1 may be a head gasket problem
One way to tell-
In the morning crank the engine fast with the key just a few revolutions and if it starts, turn it off quickly.
Pull out the number one plug.
Smell it for antifreeze.
You could also see if you can taste antifreeze on the plug surface.
If you have antifreeze, then replace the head gaskets on both cylinder heads.
May as well.
The job is so brutal and expensive - do both heads.
I had a misfire on #1 cylinder. Turned out to be the head gasket.
If you can get this truck started, then take off the cap to the expansion tank where you put the coolant in.
If the truck pushes out coolant - then this is a bad sign.
If you hear the water fall sound while driving - this is air in your heater core.
All of this from a bad head gasket with a hair line crack possibly.
Cylinder #1 there is only about 4 to 5 mm of head gasket between the firing ring seal and the coolant jacket. Pressure goes into the coolant system and antifreeze gets into the cylinder.
#6 cylinder is not near a coolant jacket.
#6 could misfire from a sticky valve.
Well, If the wires for #1 and #6 go into the same coil pack - then I would first try to replace that coil pack (there are two).
And, give that a try.
IF that does not solve it - then I am thinking #1 may be a head gasket problem
One way to tell-
In the morning crank the engine fast with the key just a few revolutions and if it starts, turn it off quickly.
Pull out the number one plug.
Smell it for antifreeze.
You could also see if you can taste antifreeze on the plug surface.
If you have antifreeze, then replace the head gaskets on both cylinder heads.
May as well.
The job is so brutal and expensive - do both heads.
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jlester@mt.gov
Discovery II
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Mar 26, 2008 09:30 PM
